1. Field of the Invention
This invention relates to an internal telephone communication system interlocked with extension telephone directory service by a Web browser, and more particularly to a method and apparatus for Web direct-dialing connection which, when receiving an incoming call via a public switched telephone network from a telephone with a Web browser, are best suited to directory call the other party to whom the user of the telephone wants to speak.
2. Description of the Related Art
A Private Branch Exchange (PBX) used in an internal telephone communication system has generally a direct-dialing function. The direct-dialing function is the function of, when the private branch exchange has received an incoming call via a public switched telephone network from an external telephone, or the calling telephone, causing an extension to receive the incoming call, that is, connecting the calling telephone to the extension. The following three types of direct-dialing functions are well known: a first function is a direct-in-line (DIL) function of causing a specific telephone or group to receive an incoming call for each physical line through which an incoming call has been received; a second function is a direct-in-dialing (DID) function of causing a specific telephone or group to receive an incoming call for each called telephone number; and a third function is a direct-in-dialing-with-additional-dial function of, after automatic response, causing the user of the calling telephone to select an extension number with the push buttons.
In an internal telephone communication system which includes a private branch exchange with such a direct-dialing function, for an external telephone to make a call to an extension telephone in the system via a public switched telephone network, the following procedure is necessary. First, the user of the external telephone dials the telephone for the group to which the other party belongs or a specific telephone capable of relaying to an extension telephone. When receiving an incoming call from the external telephone, the private branch exchange causes the telephone for the group or the specific telephone specified by the destination information, such as the dialed telephone number, to receive the incoming call.
The user (or calling user) of the external telephone or the calling telephone makes a call to the user of the telephone of the called group or the specific telephone. In the call to the called user, the calling user requests the called user to operate to transfer the call to the extension telephone allocated to the desired called party (in the case of the first or second function). When the telephone of the called group or the specific telephone has an automatic response function, an automatic response from the automatic response telephone prompts the calling user to enter the extension number of the desired called party with the push buttons. In this case, an incoming call is received by the extension telephone to which the entered extension number has been allocated (in the case of the third function). When an outside-line telephone number has been assigned to the telephone that can be used by the desired called party, the calling user can make a call to the desired called party by just dialing the outside-line telephone number.
As described above, for a telephone outside the internal telephone system to dial the telephone the called party can use via the public switched telephone network, the user of the external telephone (or the calling user) has to perform the following operations. The calling user performs an operation once to dial the telephone of the group or the specific telephone unless an outside-line telephone number has been allocated to the telephone the called party uses. Then, the calling user must ask the group or the user of the specific telephone (the called user) to transfer the call to the telephone the desired called party can use. Therefore, the communication time and the charge for a telephone call have been wasted.